1. Field of the Invention
The present invention relates to a method of manufacturing a honeycomb structure and a degreasing apparatus for a honeycomb molded body.
2. Discussion of the Background
A large number of techniques have been developed in relation to conversion of automobile exhaust gas. With an increase in traffic, however, countermeasures taken against exhaust gas have hardly been satisfactory. Not only in Japan but also globally, is automobile emission control going to be further tightened.
In order to meet such control, catalyst supports capable of treating predetermined components contained in exhaust gas are used in exhaust gas conversion systems. Further, a honeycomb structure is known as a member for such catalyst supports.
This honeycomb structure has, for example, multiple cells (through holes) extending from one end face to another end face of the honeycomb structure along its longitudinal directions. These cells are separated from each other by cell walls supporting a catalyst or cell walls formed of a catalyst. Accordingly, in the case of causing exhaust gas to flow through such a honeycomb structure, substances contained in the exhaust gas, such as HC, CO, and/or NOx, are converted by the catalyst supported by the cell walls or the catalyst forming the cell walls, so that these toxic components in the exhaust gas may be treated.
In particular, in systems called SCR (Selective Catalytic Reduction) systems, it is possible to decompose NOx in exhaust gas into nitrogen and water using ammonia. For example, WO 09/141,897 A1 discloses a honeycomb structure having a honeycomb unit containing zeolite usable in SCR systems.
The entire contents of WO 09/141,897 A1 are incorporated herein by reference.
The honeycomb structure is formed by, for example, manufacturing a honeycomb molded body by subjecting raw material paste containing inorganic particles, an inorganic binder, an organic binder, a molding aid, water, etc., to extrusion molding and thereafter degreasing and firing this honeycomb molded body.
The degreasing is performed in order to decompose and remove the organic binder and the molding aid included in the honeycomb molded body before firing the honeycomb molded body.